Imaging apparatus, method for controlling the same, and storage medium storing program

Abstract

An imaging apparatus that performs continuous imaging, includes: a focus detection unit that perform focus detection and calculates an amount of defocus in each of a plurality of imaging operations; a position detection unit that detects an image plane position corresponding to a subject position using the amount of defocus; an estimation unit that estimates a next image plane position using a plurality of pairs of data regarding the image plane position and a time at which the amount of defocus has been detected; and a turnabout determination unit that determines whether a subject is a turnabout subject, which is a subject that moves towards the imaging apparatus, changes direction of movement, and then moves away from the imaging apparatus. The number of pairs of data used for the estimation decreases based on a ratio of a highest image plane speed in past scenes to a current image plane speed.

What is claimed is: 
     
       1. An imaging apparatus that performs continuous imaging, in which a plurality of imaging operations are successively performed, the imaging apparatus comprising:
 a focus detection unit configured to perform focus detection, in which an amount of defocus is detected; 
 a position detection unit configured to detect an image plane position corresponding to a subject position using the amount of defocus; 
 an estimation unit configured to estimate a next image plane position using a plurality of pairs of data regarding the image plane position and a respective time at which the amount of defocus has been detected; and 
 a turnabout determination unit configured to determine whether a subject is a turnabout subject, which is a subject that moves towards the imaging apparatus, changes direction of movement, and then moves away from the imaging apparatus, 
 wherein, if the turnabout determination unit determines that the subject is a turnabout subject, the estimation unit sets a number of pairs of data to be used for the estimation of the next image plane position to a number smaller than when the turnabout determination unit has determined that the subject is not a turnabout subject. 
 
     
     
       2. The imaging apparatus according to  claim 1 , further comprising:
 a speed detection unit configured to detect an image plane speed corresponding to a speed of movement the subject; and 
 a storage unit configured to store, as a first speed, a higher one of a plurality of image plane speeds at times of a plurality of successive operations of the focus detection in a period in which a first control member is operated, 
 wherein, if a ratio of the first speed at a time of one of the plurality of successive operations of the focus detection in a past image plane speed in which the first control member is operated to a current image plane speed is within a first range, the estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than when the ratio is outside the first range. 
 
     
     
       3. The imaging apparatus according to  claim 2 , further comprising:
 a second estimation unit configured to estimate, after a first imaging operation but before the focus detection immediately before a second imaging operation, which is an imaging operation performed after the first imaging operation, an image plane position at a time of the second imaging operation using a plurality of pairs of data regarding the image plane position and the time, 
 wherein the first imaging operation and the second imaging operation are imaging operations during the continuous imaging, 
 wherein the focus detection unit performs the focus detection before each imaging operation during the continuous imaging, and 
 wherein, if the ratio of the first speed at the time of one of the plurality of successive operations of the focus detection in the past in which the first control member is operated to the current image plane speed is within the first range, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than when the ratio is outside the first range. 
 
     
     
       4. The imaging apparatus according to  claim 3 ,
 wherein, if a ratio of the first speed at a time of one of the plurality of successive operations of the focus detection in the past in which the first control member is operated to an image plane speed at a time of the focus detection before the first imaging operation during current continuous imaging is within the first range, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than a first certain value and, if the ratio is outside the first range, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       5. The imaging apparatus according to  claim 2 ,
 wherein, if the first speed is equal to or higher than a sixth certain value, the storage unit stores the first speed. 
 
     
     
       6. The imaging apparatus according to  claim 5 ,
 wherein, if, among image plane positions at the times of the plurality of successive operations of the focus detection performed in the period in which the first control member is operated, there is an image plane position closer to the imaging apparatus than image plane positions at times of a first operation and a last operation of the focus detection are, the storage unit stores the first speed. 
 
     
     
       7. The imaging apparatus according to  claim 4 , further comprising:
 a distance detection unit configured to detect a subject distance, 
 wherein the storage unit stores a smallest subject distance, which is a smallest one of a plurality of subject distances at the times of the plurality of successive operations of the focus detection in the past in which the first control member is operated, and 
 wherein, if a ratio of a subject distance at the time of the focus detection before the first imaging operation to the smallest subject distance is within a second range, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than the first certain value, and if the ratio is outside the second range, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       8. The imaging apparatus according to  claim 4 ,
 wherein, if the image plane speed at the time of the focus detection before the first imaging operation is lower than a third certain value, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       9. The imaging apparatus according to  claim 4 , further comprising:
 a first estimation unit configured to estimate the image plane position at the time of the second imaging operation using the plurality of pairs of data after the focus detection immediately before the second imaging operation but before the second imaging operation, 
 wherein, if a difference between the image plane position at the time of the second imaging operation estimated by the first estimation unit and the image plane position at the time of the second imaging operation estimated by the second estimation unit is equal to or larger than a fifth certain value, the first estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than the first certain value, and if the difference is smaller than the fifth certain value, the first estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       10. The imaging apparatus according to  claim 9 ,
 wherein, if a fourth certain period of time has elapsed since the number of pairs of data was set smaller than the first certain value, the first estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       11. The imaging apparatus according to  claim 5 ,
 wherein the first speed is a highest image plane speed, which is a highest one of the plurality of image plane speeds at the times of the plurality of successive operations of the focus detection in the period in which the first control member is operated. 
 
     
     
       12. The imaging apparatus according to  claim 1 , further comprising:
 a focus detection unit configured to perform focus detection, in which the amount of defocus is detected, wherein the focus detection unit performs the focus detection before each imaging operation during the continuous imaging; 
 a position detection unit configured to detect the image plane position corresponding to the subject position using the amount of defocus; 
 a second estimation unit configured to estimate, after a first imaging operation but before the focus detection immediately before a second imaging operation, which is an imaging operation performed after the first imaging operation, an image plane position at a time of the second imaging operation using a plurality of pairs of data regarding the image plane position and the time at which the amount of defocus has been detected; and 
 a first estimation unit configured to estimate the image plane position at the time of the second imaging operation using the plurality of pairs of data after the focus detection immediately before the second imaging operation but before the second imaging operation, 
 wherein the first imaging operation and the second imaging operation are imaging operations during the same continuous imaging, and 
 wherein the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position based on a difference between a result of the estimation performed by the first estimation unit and a result of the estimation performed by the second estimation unit. 
 
     
     
       13. The imaging apparatus according to  claim 12 ,
 wherein, if a difference between the image plane position at the time of the second imaging operation estimated by the second estimation unit and the image plane position at the time of the second imaging operation estimated by the first estimation unit is equal to or larger than a fifth certain value, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than the first certain value, and if the difference is smaller than the fifth certain value, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       14. The imaging apparatus according to  claim 13 ,
 wherein, if the image plane position at the time of the second imaging operation estimated by the second estimation unit is closer, by the fifth certain value or more, to the imaging apparatus than the image plane position at the time of the second imaging operation estimated by the first estimation unit is, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than the first certain value, and if the image plane position at the time of the second imaging operation estimated by the second estimation unit is not closer, by the fifth certain value or more, to the imaging apparatus than the image plane position at the time of the second imaging operation estimated by the first estimation unit is, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       15. The imaging apparatus according to  claim 13 , further comprising:
 a speed detection unit configured to detect an image plane speed corresponding to a speed of the subject, 
 wherein, if an image plane speed at a time of the focus detection before the first imaging operation is equal to or higher than a third certain value, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than the first certain value, and if the image plane speed is lower than the third certain value, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       16. The imaging apparatus according to  claim 12 ,
 wherein, if a fourth certain period of time has elapsed since the number of pairs of data was set smaller than the first certain value, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the first certain value. 
 
     
     
       17. The imaging apparatus according to  claim 12 , further comprising:
 a storage unit configured to store, as a first speed, a higher one of a plurality of image plane speeds at times of a plurality of successive operations of the focus detection in a period in which the first control member is operated, 
 wherein, if a ratio of the first speed to the image plane speed at a time of the focus detection before the first imaging operation is within a first range, the first estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than when the ratio is outside the first range. 
 
     
     
       18. The imaging apparatus according to  claim 17 ,
 wherein, if the ratio of the first speed to the image plane speed at the time of the focus detection before the first imaging operation is within the first range, the first estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position smaller than a second certain value, and if the ratio is outside the first range, the second estimation unit sets the number of pairs of data to be used for the estimation of the next image plane position to the second certain value. 
 
     
     
       19. A method for controlling an imaging apparatus that performs continuous imaging, in which a plurality of imaging operations are successively performed, the method comprising the steps of:
 performing focus detection, in which an amount of defocus is detected; 
 detecting an image plane position corresponding to a subject position using the amount of defocus; 
 estimating a next image plane position using a plurality of pairs of data regarding the image plane position and a respective time at which the amount of defocus has been detected; and 
 determining whether a subject is a turnabout subject, which is a subject that moves towards the imaging apparatus, changes direction of movement, and then moves away from the imaging apparatus, 
 wherein, if it is determined, in the determining step, that the subject is a turnabout subject, the estimating step sets a number of pairs of data to be used for the estimating of the next plane to a number smaller than when the determining step has determined that the subject is not a turnabout subject. 
 
     
     
       20. A computer-readable storage medium storing a program for causing a computer to perform a method for controlling an imaging apparatus that performs continuous imaging, in which a plurality of imaging operations are successively performed, the method comprising the steps of:
 performing focus detection, in which an amount of defocus is detected; 
 detecting an image plane position corresponding to a subject position using the amount of defocus; 
 estimating a next image plane position using a plurality of pairs of data regarding the image plane position and a respective time at which the amount of defocus has been detected; and 
 determining whether a subject is a turnabout subject, which is a subject that moves towards the imaging apparatus, changes direction of movement, and then moves away from the imaging apparatus, 
 wherein, if it is determined, in the determining step, that the subject is a turnabout subject, the estimating step sets a number of pairs of data to be used for the estimating of the next plane to a number smaller than when the determining step has determined that the subject is not a turnabout subject. 
 
     
     
       21. An imaging apparatus that performs continuous imaging, in which a plurality of imaging operations are successively performed, the imaging apparatus comprising:
 a focus detection unit configured to perform focus detection and to calculate an amount of defocus; 
 a position detection unit configured to detect an image plane position corresponding to a subject position using the amount of defocus; 
 a speed detection unit configured to detect an image plane speed corresponding to a speed of the subject; 
 a storage unit configured to store, as a first speed, a higher one of a plurality of image plane speeds at times of a plurality of successive operations of the focus detection in a period in which a first control member is operated; and 
 a turnabout determination unit configured to determine whether the subject is a turnabout subject, which is a subject that moves towards the imaging apparatus, changes direction of movement, and then moves away from the imaging apparatus, 
 wherein, if a ratio of the first speed at a time of one of the plurality of successive operations of the focus detection in the period in which the first control member is operated to a current image plane speed is within a first range, the turnabout determination unit determines that the subject is a turnabout subject, and if the ratio is outside the first range, the turnabout determination unit determines that the subject is not a turnabout subject. 
 
     
     
       22. An imaging apparatus that performs continuous imaging, in which a plurality of imaging operations are successively performed, the imaging apparatus comprising:
 a focus detection unit configured to perform focus detection, in which an amount of defocus is detected, wherein the focus detection unit performs the focus detection before each imaging operation during the continuous imaging; 
 a position detection unit configured to detect an image plane position corresponding to a subject position using the amount of defocus; 
 a second estimation unit configured to estimate, after a first imaging operation but before the focus detection immediately before a second imaging operation, which is an imaging operation performed after the first imaging operation, an image plane position at a time of the second imaging operation using a plurality of pairs of data regarding the image plane position and a time at which the amount of defocus has been detected, 
 a first estimation unit configured to estimate the image plane position at the time of the second imaging operation using the plurality of pairs of data after the focus detection immediately before the second imaging operation but before the second imaging operation; and 
 a turnabout determination unit configured to determine whether a subject is a turnabout subject, which is a subject that moves towards the imaging apparatus, changes direction of movement, and then moves away from the imaging apparatus, 
 wherein the first imaging operation and the second imaging operation are imaging operations during the continuous imaging, and 
 wherein the turnabout determination unit determines whether the subject is a turnabout subject based on a difference between a result of the estimation performed by the first estimation unit and a result of the estimation performed by the second estimation unit.